When two communication terminal apparatuses initiate calls almost simultaneously so that each of the communication terminal apparatuses will initiate a call to the other communication terminal apparatus as a call reception destination, for the initiation of calls from both of the communication terminal apparatuses, the calls fail to be answered by the call reception destinations in some cases. In such a case, if a user of one of the communication terminal apparatuses waits for an incoming call from the other communication terminal apparatus and a user of the other communication terminal apparatus initiates the call, it is possible to smoothly start a telephone call. This is disclosed in, for example, Japanese Laid-open Patent Publication No. 2005-130029.